Digital displays and touchscreens are increasingly prominent in consumer electronics, telecommunications, and computing. Unfortunately, the materials used for these displays are prone to fracturing and cracking, which may render the device unusable. Once damaged, the screen is expensive to replace. Protective cases and covers that are currently marketed can be bulky and expensive. This technology is a method to prevent crack propagation in display screens through the deposition of a thin material layer in a patterned structure on the screen. By containing cracks within the small substructures of the patterned layer, widespread crack propagation is prevented. This protective layer can be applied using conventional lithography techniques during the display fabrication process, increasing the durability and lifetime of the screen.
Almost all conventional displays are composed of brittle materials that exhibit significant crack propagation. Thus, a concentrated impact to a small portion of the screen can induce cracking throughout the entire surface. However, crack propagation can be controlled using a thermal stress technique to steer the crack along a predefined path. This technology applies a multitude of thermal stress control structures to the surface of a brittle material using lithography. After coating, cracks that are induced in the screen are directed and contained within the microfabricated structures. The applied layer can be constructed using a variety of different materials, including polymers, hafnium dioxide, indium tin oxide, or graphene. Furthermore, this layer does not significantly impact screen visibility; a graphene layer for instance only absorbs 2% of the incoming light.
A prototype of this technology has been developed by patterning silicon dioxide onto a silicon substrate using photolithography. Crack propagation was impeded by the silicon dioxide and could be directed into arbitrary shapes that were specified during microfabrication.
Patent Pending
Tech Ventures Reference: IR CU15166